In the prior art, metal working machines for turning workpieces require a machinist to calculate a radius to be cut based on drawings or specifications stated in diameters. Once the radius is known, the machinist must rely on vernier calipers, micrometers and gauges to measure the cut made on the workpiece. The ideal model for any machine tool is a device which provides a direct indicator reading, such as a jig bore, which gives the machinist an accurate way of measuring the machining of the workpiece.
However, a typical machine tool such as a lathe, mill or boring machine may not include built-in indicators. At best, short of expensive tape attachments, the machines have precision threaded lead screws where accuracy is dependent on counting the number of turns of a handle.
While dial indicators can be attached to lathes to measure the movement of a cutting tool along the longitudinal axis of the workpiece, lathes have no provision for the mounting of a cross slide indicator for measuring the dimensions of the radial cuts. Milling machines are designed such that an indicator can be easily mounted. However, they are not designed for measuring in both cutting directions. Further, devices for measuring exist for automatic lathes which may be used for high production; but these devices are prohibitively expensive for the small machine shop and for low production.
In today's economy, there is a shortage of vital skills in the machine tool industry. This shortage of specialized tradespeople such as skilled machinists, jig-and-fixture experts, tool-and-die makers, and pattern makers will be exasperated by the biggest peacetime defense buildup in U.S. history under the programs of the present administration.